October 20, 2019, 05:53:54 PM
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Topic: electrolysis of PdCl2 (aq ) and AgNO3 (aq) solutions .masses of Pd and Ag ?  (Read 7611 times)

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Offline sam

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The same amount of electricity (same number of moles of electrons) is used to
carry out the electrolysis of PdCl2 (aq ) and AgNO3 (aq) solutions in separate cells.
The masses of Pd and Ag produced were measured and compared. Which of the
following is true about the mass of Pd produced?

A. The mass of Pd produced is not related to the mass of Ag.
B. The mass of Pd produced is approximately half that of Ag.
C. The mass of Pd produced is approximately twice that of Ag.
D. The mass of Pd produced is approximately the same as that of Ag.

i have no idea from where i should start. could you help me figure it out?


thanks in advance

Offline Borek

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You have to compare number of electrons needed to reduce both ions and to compare both molar masses.

http://en.wikipedia.org/wiki/Faraday's_law_of_electrolysis
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Offline BaO

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because Pd and Ag will be produced ,there will be 2 half-reactions : Pd2++2e- ->Pd
                                                                                              Ag+ +e- -> Ag

according to Faraday's law,mPd=  #of moles of 2e , similarly to mass of Ag? (i'm not very sure)
so i think the answer is C. what you think?

Offline Will

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so i think the answer is C. what you think?

I would say the answer is B.

Offline sam

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Quote
I would say the answer is B

why? isnt mass of Pd = moles of 2e while mAg=e
 
« Last Edit: August 03, 2006, 07:45:51 PM by sam »

Offline sam

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oh, i get it .
 mPd= moles of e-/2
 mAg= moles of e- and because there are the same numbers of moles of e-, therefore the answer is B

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